Sudoku · cooperative mystery

Sudoku: Mystery Club — play online with friends

Sudoku: Mystery Club combines classic 9×9 Sudoku with a mystery to solve. Fill a shared grid, uncover evidence and compare witness statements. Enjoy a solo case or invite up to three friends with a room code. No bots are added.

Play for free

The game opens in a new tab. An internet connection is required.

Players: 1–4 human players
Mode: Solo investigations or online cooperative rooms
Devices: Desktop and mobile · browser
Game languages: Russian, English, Chinese

How to play: Sudoku: Mystery Club

Choose Play solo or Create a room, then select an unlocked case and difficulty. Share the room code with friends.
Fill every row, column and 3×3 box with the digits 1–9 without repetition. Use private notes and hints that explain a logical step.
Clues unlock at 25%, 60% and 100% completion. Read the file and updated testimony; a nervous manner alone is not evidence.
After solving the grid, decide who acted and why. Agree on a theory as a team. A correct explanation unlocks the full story and next case.

Controls

Mouse or touch

Select a cell, then use the number pad. The case file holds clues, testimony and your team’s contributions.

Keyboard

Use 1–9 to enter digits, arrow keys to navigate, N for notes and Backspace to clear private notes.

Tips for your first game

Start with Introductory difficulty for more given numbers. Every generated puzzle has one solution and can be completed with supported logical steps.
Work on different cells together. A colour and number identify each correct move’s author. Mistakes do not erase the team’s progress.
Sign in to Igrodvor before playing to keep your progress across devices. Guest profiles remain separate.

A shared Sudoku and your case file

Fill a shared grid: correct moves show their authors and unlock clues in the case file

Compare original and updated testimony before agreeing on your explanation

Frequently asked questions

Can I play alone without a bot?

Yes. Solo mode offers the same stories without an automatic teammate. Shared rooms support up to four people.

Do I need to download Sudoku?

No. Play in a desktop or mobile browser. An internet connection is needed to confirm moves and save progress.

How many cases and difficulties are there?

Six stories take you to a conservatory, railway station, sweet shop, lighthouse, music museum and observatory. Choose Introductory, Standard or Challenging grids.

What happens if I make a mistake?

An incorrect digit does not fill the cell. A wrong final theory lets you review the evidence and try again without solving the grid again or waiting.

One profile for all your games

You can start as a guest. Sign in to Igrodvor before launching a game to use the same profile and view saved results across devices. Guest progress and profiles from other gaming platforms stay separate.